Question

def second_index(a_list, number): Accepts a list of integers and an integer, and returns the index of the SECOND occurrence of the integer in the list. It returns None if the number does not occur two or more times in the list. Example 1: second_index ([2,34,3,45,34,45,3,3), 3) returns 6 Example 2: second_index( [2,34,3,45,34,45,3,3), 45) returns 5 Example 3: second_index ( [2,34,3,45,134,45,3,3), 134) returns None Example 4: second_index( [2,34,3,45, 134,45,3,3), 100) returns None return None def hasEveryLetter(s): #s is a string Returns True if every letter of the (lowercase) alphabet can be found (at least once) in s, False otherwise return None

Answer 1

Code with explanation:

def second_index(a_list,number):
#list of all occurance
lst=[i for i, n in enumerate(a_list) if n == number ]
if len(lst)>1:
return lst[1]
else:
return None
  
print(second_index([2,34,3,45,34,45,3,3],3))
print(second_index([2,34,3,45,34,45,3,3],45))
print(second_index([2,34,3,45,134,45,3,3],134))
print(second_index([2,34,3,45,134,45,3,3],100))

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screenshot of output with code:

In [10]: def second_index(a_list, number): #list of all occurance 1st=[i for i, n in enumerate(a_list) if n == number ] if len(1st)>1: return Ist[1] else: return None print(second_index([2,34,3,45,34,45,3,3),3)) print(second_index([2,34,3,45,34,45,3,3),45)) print(second_index([2,34,3,45,134,45,3,3), 134)) print(second_index([2,34,3,45,134,45,3,3), 100)) 6 5 None None

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Code with explanation:

def hasEveryLetter(s):
for x in s:
#check if the letter is lower
if x.islower():
#count the number of occurance of each letter
#in given string
cnt=[i for i, n in enumerate(s) if n == x]
#if occurance is greater than 1
#return False
if(len(cnt)>1):
return False
return True

print(hasEveryLetter("Apple"))
print(hasEveryLetter("aPPle"))
print(hasEveryLetter("bankruptcy"))
print(hasEveryLetter("Demography"))

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screenshot of output with code:

In [20]: def hasEveryLetter(s): for x in s: #check if the letter is Lower if x.islower(): #count the number of occurance of each Letter #in given string cnt=[i for i, n in enumerate(s) if n == x] #if occurance is greater than 1 #return false if(len(cnt)>1): return false return True - print(hasEveryLetter("Apple")) print(hasEvery Letter("bankruptcy")) print(hasEveryLetter("Demography")) False True True

In [21]: def hasEveryLetter(s): for x in s: #check if the letter is Lower if x.islower(): #count the number of occurance of each Letter #in given string cnt=[i for i, n in enumerate(s) if n x] #if occurance is greater than 1 #return false if(len(cnt) >1): return false return True print(hasEveryLetter("Apple")) print(hasEveryLetter("aPPle")) print(hasEvery Letter("bankruptcy")) print(hasEveryLetter("Demography"))|| False True True True